Fifteen Fascinating Facts about the Sun
The Sun is the Solar System's one and only star. Here are twelve star-studded facts about it!
The Sun is the closest star to Earth
The Sun is the closest star to Earth. It is roughly about 150 million kilometres or 93 million miles from Earth. That distance is also known as 1 Astronomical Unit (AU). If you could take a non-stop flight from Earth to the Sun in a typical jumbo jet flying at its normal speed (about 870 kilometres or 540 miles an hour), it would 19 to 20 years to reach your destination. You wouldn't be able to complain about the heat when you got there though!
The next star out from the Sun is Proxima Centauri
The next nearest star to Earth after the Sun is Proxima Centauri, which isn't really near at all. It's over 40 million million kilometres (25 million million miles) away. This is 268,770 Astronomical Units away which means that Proxima Centauri is 268,770 times further away from Earth than the Sun is. Not sure if this counts as a fact about the Sun, but the Sun gets a mention in it, so it'll do.
Light from the Sun takes 8 minutes to reach Earth
Light from the Sun takes 8 minutes to reach Earth. This means people on Earth see the Sun as it was 8 minutes ago. Over at Neptune, the solar system's most distant planet, the Sun's light takes four hours to reach it. If we want to compare the Sun with Proxima Centauri again, light from there takes 4.25 years to reach Earth.
The Sun is a yellow dwarf star. It isn't actually yellow!
The Sun is officially classified as a G-type Main Sequence star. It is also commonly classified as a yellow dwarf star. The Sun isn't actually yellow, it's white.
The Sun's power is generated at its core
The Sun generates its immense power by converting hydrogen into helium through a process called nuclear fusion. This process happens in the Sun's core with the energy taking up to 170,000 years to reach the Sun's surface where it escapes as heat, light and other forms of energy.
The Sun is a giant ball of gas
About 73% of the Sun is made up of hydrogen. Most of the rest of it is helium. In about 5 billion years, when the Sun begins running out of hydrogen, it will start using up its helium supply, fusing that instead. This will cause it a expand in size and become a red giant, consuming Mercury and Venus and ending any chances of life being possible on Earth. It will eventually shed its outer layers and become a dim white dwarf.
Most of the contents of the solar system are contained within the Sun
The Sun is by far the largest object in the solar system and contains almost 99.8 to 99.9% of the entire mass of it. The remaining 0.01 to 0.02% are the solar system's planets, moons, asteroids, meteoroids and comets. These are all held in place by the Sun's gravitational pull.
The Sun is 109 times wider than Earth, 10 times wider than Jupiter
The Sun's diameter of about 1.4 million kilometres (864,000 miles) is much greater than Earth's of 12,742 km (7,918 miles) and Jupiter's of 139,820 km (86,880 miles). The volume of the Sun is so great that 1.3 million Earths could fit inside it.
Earth's spin is what causes the Sun to rise in the east and set in the west
The Sun always rises in the east and sets in the west. It appears to travel across the sky very slowly throughout the day. This is the same in both the Northern and Southern hemispheres. The Sun rising in the east, travelling across the sky and setting in the west is because the Earth is constantly spinning and not because the Sun itself is actually moving in relation to Earth.
There are billions of stars like the Sun
The Sun is just one of billions of stars in the Milky Way galaxy. It is located about halfway between the centre of the Milky Way and its outer edge at a distance of around 27,000 light years from the centre. The objects in the Milky Way all travel around the centre of the galaxy, with the Sun taking around 230 million years to complete an orbit, travelling at 792,000 kilometres per hour or 493,000 miles per hour.
It was once believed that the Sun WASN'T at the centre of the solar system
The Sun is situated at the centre of the solar system and every other object in the solar system orbits it. This has only been accepted as the case for the last 500 years or so. Prior to that, it was taught that Earth was the centre of the Universe and everything else orbited it. The Moon was seen to be the closest object, followed by Mercury, Venus, the Sun, Mars, Jupiter and then Saturn. Anybody suggesting otherwise could find themselves in trouble, so most people just accepted what they were told and got on with their lives. For the Polish astronomer, Nicholas Copernicus, an Earth-centred system didn't make sense to him, so he proposed a system which put the Sun at the centre and everything else around it. Although he had finished writing out his ideas by 1530, he waited until he was nearly dead in 1543 before he published them.
The Sun had an explosive and exciting beginning
Like every star in the universe, the Sun was formed from a huge swirling cloud of gas called a nebula. About 4.6 billions years ago, that cloud of gas collapsed in on itself. Most of its contents were pulled to its centre, becoming more and more squashed together to the point that they heated up and eventually ignited into a new star. The remaining gas and dust materials spinning around the Sun went onto form the planets and all of the other solar system objects.
The Sun has spots - cooler and darker patches that represent trapped energy
Sunspots are patches on the Sun's surface where the Sun's energy is blocked from escaping from it. They cause those areas to be darker and cooler. When energy is blocked from escaping at sunspots, it has to escape elsewhere and bursts out of the sun as solar flares or coronal mass ejections.
The Sun doesn't have a solid surface
The Sun's visible surface is called its photosphere. Temperatures at this surface reach 5,500 °C (9,900 °F). In sunspots, temperatures can dip as low as 2,700 °C ( 4,200 °C). Above the Sun's visible surface is its corona. This can only be seen in a total solar eclipse. Temperatures in the corona are much higher than at the Sun's surface, exceeding 1 million °C (1.8 million °F).
Sometimes the Moon blocks the view of the Sun from Earth
A total eclipse occurs when the Moon is position exactly in between Earth and the Sun, and light from the Sun is blocked from reaching Earth. This can only happen because the Sun is 400 times larger than the Moon, but it is also 400 times further away so, from Earth, both objects appear to be the same size.